1. Field of the Invention
The present invention relates to a method for determining spatial coherences among features of an object.
2. Description of the Related Art
Many current methods of object exploration involve the analysis of data fields for observed properties of the object such as the strength of physical fields (e.g., magnetic, radioactive, gravitational, infrared, and electromagnetic) to deduce the location and range of features within the object. There are two principal approaches for analyzing data fields to detect features within an object. The first approach is pattern recognition which involves comparing a data field of an object to other data fields of objects known to possess a desired feature. Patterns common to the data fields indicate the presence of the desired feature in the object under investigation. The second approach is an "expert system" which classifies data according to a complex scheme that employs many variables and uses decision-making rules subjectively selected by an investigator based on his experience, knowledge, and intuition.
Although pattern recognition methods and "expert system" technology are often adequate to locate features within an object, there are disadvantages to those techniques. They frequently produce biased outcomes because pattern recognition is heavily influenced by past occurrences of features and "expert systems" are dependent upon the feature selection criteria chosen by the investigator. When a biased outcome occurs, more meaningful features within an object may have been suppressed in favor of less meaningful ones that happen to correlate with a previously observed feature or a feature predicted to be meaningful by the investigator. Furthermore, the aforementioned techniques are directive because judgments of correlation between features in the object are made based upon pre-existing features. Thus, at each opportunity for deciding whether sufficient correlation exists, incremental preferences for the pre-existing feature are introduced. Accordingly, neither technique permits natural meaningful features within an object to be detected without the influence of a pre-existing feature selected beforehand by the investigator.
U.S. Pat. No. 5,606,499, which was issued to Ostrovsky on Feb. 25, 1997, discloses a method and apparatus that improves over pattern recognition and "expert systems" by eliminating preferences toward pre-existing features. Preferences are eliminated because features within an object are located without comparing the object to a pre-existing feature or using a feature generated by an investigator. Instead, data fields of an object are examined to determine structural organization within the data fields themselves, which typically indicates features that are significant.
In addition, the object may be compared to a target to determine if it exhibits qualities of the target. This identifies structures within the object similar to the target, however, it fails to furnish an indication of coherences among the structures within the object. Coherence information is important because it provides a pointer to the actual location of the structures within the object creating a feature similar to the target. Accordingly, a method and apparatus that produce coherence information for structures within an object will enhance the likelihood of locating features within an object.